• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.2
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• pp.159-169
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• 2009

In this study, the antibacterial activity, antioxidative effects, inhibitory effects on tyrosinase, inhibitory effects on elastase, and components of Quercus acutissima Carruth leaf extracts were investigated. MIC values of ethyl acetate fraction from Q. acutissima Carruth leaf on P. acnes, S. aureus, P. ovale, and E. coli were 0.13 %, 0.25 %, 0.13 % and 0.25 %, respectively. The results showed that the antibacterial activity of the ethyl acetate fraction was the highest in the S. aureus, P. acnes, and P. ovale. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity ($FSC_{50}$) of extract/fractions of Q. acutissima Carruth. leaf was in the order: 50 % ethanol extract (12.13 ${\mu}g/mL$) < ethyl acetate fraction (7.07 ${\mu}g/mL$) < deglycosylated flavonoid aglycone fraction (6.20 ${\mu}g/mL$). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of some Q. acutissima Carruth leaf extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The order of ROS scavenging activity was 50 % ethanol extract ($OSC_{50}$, 1.81 ${\mu}g/mL$) < ethyl acetate fraction (1.70 ${\mu}g/mL$) < deglycosylated flavonoid aglycone fraction (0.70 ${\mu}g/mL$). Deglycosylated flavonoid aglycone fraction showed the most prominent scavenging activity. The protective effects of extract/fractions of Q. acutissima Carruth leaf on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The Q. acutissima Carruth leaf extracts suppressed photohemolysis in a concentration dependent manner, particularly deglycosylated flavonoid aglycone fraction exhibited the most prominent celluar protective effect (${\tau}50$, 220.00 min at 25 ${\mu}g/mL$). Aglycone fractions obtained from the deglycosylation reaction of ethyl acetate fraction among the Q. acutissima Carruth leaf extracts, showed 3 bands (QA 1, QA2 and QA3) on TLC. TLC chromatogram of ethyl acetate fraction of Q. Carruth. leaf extract revealed 4 bands (QA 1 ${\sim}$ QA 4), Among them, kaempferol (QA 1), quercetin (QA 2), and gallic acid (QA 3) were identified. The inhibitory effect ($IC_{50}$) of aglycone fraction on tyrosinase was 65.7 ${\mu}g/mL$. The inhibitory effect ($IC_{50}$) of aglycone fraction on elastase was 24.50 ${\mu}g/mL$. These results indicate that extract/fractions of Q. acutissima Carruth. can functionized as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against ROS. Extract/fractions of Q. acutissima Corruth can be applicable to new functional cosmetics for antioxidant, antiaging, antibacterial activity.